<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>

        *{
            margin: 0;
            padding: 0;
        }
        .box{
            /* 定位:  position  */
            position: relative;
            left: 50px;
            top: 50px;
            width: 100px;
            height: 100px;
            background-color: red;
        }
    </style>
</head>
<body>
    <!-- relative   相对定位

    参照物:  自身原来的位置 -->

    <div class="box">

    </div>
</body>
</html>